Showing papers by "General Electric published in 2013"

Highly multiplexed single-cell analysis of formalin-fixed, paraffin-embedded cancer tissue

Abstract: Limitations on the number of unique protein and DNA molecules that can be characterized microscopically in a single tissue specimen impede advances in understanding the biological basis of health and disease. Here we present a multiplexed fluorescence microscopy method (MxIF) for quantitative, single-cell, and subcellular characterization of multiple analytes in formalin-fixed paraffin-embedded tissue. Chemical inactivation of fluorescent dyes after each image acquisition round allows reuse of common dyes in iterative staining and imaging cycles. The mild inactivation chemistry is compatible with total and phosphoprotein detection, as well as DNA FISH. Accurate computational registration of sequential images is achieved by aligning nuclear counterstain-derived fiducial points. Individual cells, plasma membrane, cytoplasm, nucleus, tumor, and stromal regions are segmented to achieve cellular and subcellular quantification of multiplexed targets. In a comparison of pathologist scoring of diaminobenzidine staining of serial sections and automated MxIF scoring of a single section, human epidermal growth factor receptor 2, estrogen receptor, p53, and androgen receptor staining by diaminobenzidine and MxIF methods yielded similar results. Single-cell staining patterns of 61 protein antigens by MxIF in 747 colorectal cancer subjects reveals extensive tumor heterogeneity, and cluster analysis of divergent signaling through ERK1/2, S6 kinase 1, and 4E binding protein 1 provides insights into the spatial organization of mechanistic target of rapamycin and MAPK signal transduction. Our results suggest MxIF should be broadly applicable to problems in the fields of basic biological research, drug discovery and development, and clinical diagnostics.

An analysis of several heuristics for the traveling salesman problem.

Abstract: Several polynomial time algorithms finding “good,” but not necessarily optimal, tours for the traveling salesman problem are considered. We measure the closeness of a tour by the ratio of the obtained tour length to the minimal tour length. For the nearest neighbor method, we show the ratio is bounded above by a logarithmic function of the number of nodes. We also provide a logarithmic lower bound on the worst case. A class of approximation methods we call insertion methods are studied, and these are also shown to have a logarithmic upper bound. For two specific insertion methods, which we call nearest insertion and cheapest insertion, the ratio is shown to have a constant upper bound of 2, and examples are provided that come arbitrarily close to this upper bound. It is also shown that for any n≥8, there are traveling salesman problems with n nodes having tours which cannot be improved by making n/4 edge changes, but for which the ratio is 2(1−1/n).

Analyzing graphs with node differential privacy

Abstract: We develop algorithms for the private analysis of network data that provide accurate analysis of realistic networks while satisfying stronger privacy guarantees than those of previous work. We present several techniques for designing node differentially private algorithms, that is, algorithms whose output distribution does not change significantly when a node and all its adjacent edges are added to a graph. We also develop methodology for analyzing the accuracy of such algorithms on realistic networks. The main idea behind our techniques is to 'project' (in one of several senses) the input graph onto the set of graphs with maximum degree below a certain threshold. We design projection operators, tailored to specific statistics that have low sensitivity and preserve information about the original statistic. These operators can be viewed as giving a fractional (low-degree) graph that is a solution to an optimization problem described as a maximum flow instance, linear program, or convex program. In addition, we derive a generic, efficient reduction that allows us to apply any differentially private algorithm for bounded-degree graphs to an arbitrary graph. This reduction is based on analyzing the smooth sensitivity of the 'naive' truncation that simply discards nodes of high degree.

Deep Learning for Chinese Word Segmentation and POS Tagging

Abstract: This study explores the feasibility of performing Chinese word segmentation (CWS) and POS tagging by deep learning. We try to avoid task-specific feature engineering, and use deep layers of neural networks to discover relevant features to the tasks. We leverage large-scale unlabeled data to improve internal representation of Chinese characters, and use these improved representations to enhance supervised word segmentation and POS tagging models. Our networks achieved close to state-of-theart performance with minimal computational cost. We also describe a perceptron-style algorithm for training the neural networks, as an alternative to maximum-likelihood method, to speed up the training process and make the learning algorithm easier to be implemented.

Aromatic polythiourea dielectrics with ultrahigh breakdown field strength, low dielectric loss, and high electric energy density.

Abstract: The promise of aromatic, amorphous, polar polymers containing high dipolar moments with very low defect levels is demonstrated for future dielectric materials with ultrahigh electric-energy density, low loss at high applied fields, and ultrahigh breakdown strengths Specifically, aromatic polythiourea films exhibit an ultrahigh breakdown field (>1 GV m(-1)), which results in an energy density of ≈22 J cm(-3), as well as a low loss

Selective Tumor Cell Targeting by the Disaccharide Moiety of Bleomycin

Abstract: In a recent study, the well-documented tumor targeting properties of the antitumor agent bleomycin (BLM) were studied in cell culture using microbubbles that had been derivatized with multiple copies of BLM. It was shown that BLM selectively targeted MCF-7 human breast carcinoma cells but not the "normal" breast cell line MCF-10A. Furthermore, it was found that the BLM analogue deglycobleomycin, which lacks the disaccharide moiety of BLM, did not target either cell line, indicating that the BLM disaccharide moiety is necessary for tumor selectivity. Not resolved in the earlier study were the issues of whether the BLM disaccharide moiety alone is sufficient for tumor cell targeting and the possible cellular uptake of the disaccharide. In the present study, we conjugated BLM, deglycoBLM, and BLM disaccharide to the cyanine dye Cy5**. It was found that the BLM and BLM disaccharide conjugates, but not the deglycoBLM conjugate, bound selectively to MCF-7 cells and were internalized. The same was also true for the prostate cancer cell line DU-145 (but not for normal PZ-HPV-7 prostate cells) and for the pancreatic cancer cell line BxPC-3 (but not for normal SVR A221a pancreas cells). The targeting efficiency of the disaccharide was only slightly less than that of BLM in MCF-7 and DU-145 cells and comparable to that of BLM in BxPC-3 cells. These results establish that the BLM disaccharide is both necessary and sufficient for tumor cell targeting, a finding with obvious implications for the design of novel tumor imaging and therapeutic agents.

Approaches for Reducing the Computational Cost of Interval Type-2 Fuzzy Logic Systems: Overview and Comparisons

Abstract: Interval type-2 fuzzy logic systems (IT2 FLSs) have demonstrated better abilities to handle uncertainties than their type-1 (T1) counterparts in many applications; however, the high computational cost of the iterative Karnik-Mendel (KM) algorithms in type-reduction means that it is more expensive to deploy IT2 FLSs, which may hinder them from certain cost-sensitive real-world applications. This paper provides a comprehensive overview and comparison of three categories of methods to reduce their computational cost. The first category consists of five enhancements to the KM algorithms, which are the most popular type-reduction algorithms to date. The second category consists of 11 alternative type-reducers, which have closed-form representations and, hence, are more convenient for analysis. The third category consists of a simplified structure for IT2 FLSs, which can be combined with any algorithms in the first or second category for further computational cost reduction. Experiments demonstrate that almost all methods in these three categories are faster than the KM algorithms. This overview and comparison will help researchers and practitioners on IT2 FLSs choose the most suitable structure and type-reduction algorithms, from a computational cost perspective. A recommendation is given in the conclusion.

Modelling the physics in the iterative reconstruction for transmission computed tomography

Abstract: There is an increasing interest in iterative reconstruction (IR) as a key tool to improve quality and increase applicability of x-ray CT imaging. IR has the ability to significantly reduce patient dose; it provides the flexibility to reconstruct images from arbitrary x-ray system geometries and allows one to include detailed models of photon transport and detection physics to accurately correct for a wide variety of image degrading effects. This paper reviews discretization issues and modelling of finite spatial resolution, Compton scatter in the scanned object, data noise and the energy spectrum. The widespread implementation of IR with a highly accurate model-based correction, however, still requires significant effort. In addition, new hardware will provide new opportunities and challenges to improve CT with new modelling.

GBM Volumetry using the 3D Slicer Medical Image Computing Platform

Abstract: Volumetric change in glioblastoma multiforme (GBM) over time is a critical factor in treatment decisions. Typically, the tumor volume is computed on a slice-by-slice basis using MRI scans obtained at regular intervals. (3D)Slicer - a free platform for biomedical research - provides an alternative to this manual slice-by-slice segmentation process, which is significantly faster and requires less user interaction. In this study, 4 physicians segmented GBMs in 10 patients, once using the competitive region-growing based GrowCut segmentation module of Slicer, and once purely by drawing boundaries completely manually on a slice-by-slice basis. Furthermore, we provide a variability analysis for three physicians for 12 GBMs. The time required for GrowCut segmentation was on an average 61% of the time required for a pure manual segmentation. A comparison of Slicer-based segmentation with manual slice-by-slice segmentation resulted in a Dice Similarity Coefficient of 88.43 ± 5.23% and a Hausdorff Distance of 2.32 ± 5.23 mm.

The Science, Technology, and Implementation of TiAl Alloys in Commercial Aircraft Engines

Abstract: The present article will describe the science and technology of titanium aluminide (TiAl) alloys and the engineering development of TiAl for commercial aircraft engine applications. The GEnxTM engine is the first commercial aircraft engine that is flying titanium aluminide (alloy 4822) blades and it represents a major advance in propulsion efficiency, realizing a 20% reduction in fuel consumption, a 50% reduction in noise, and an 80% reduction in NOx emissions compared with prior engines in its class. The GEnxTM uses the latest materials and design processes to reduce weight, improve performance, and reduce maintenance costs. GE’s TiAl low-pressure turbine blade production status will be discussed along with the history of implementation. In 2006, GE began to explore near net shape casting as an alternative to the initial overstock conventional gravity casting plus machining approach. To date, more than 40,000 TiAl low-pressure turbine blades have been manufactured for the GEnxTM 1B (Boeing 787) and the GEnxTM 2B (Boeing 747-8) applications. The implementation of TiAl in other GE and non-GE engines will also be discussed.

Systems and methods for combined wireless power charging and network pairing

Abstract: A system includes a first network member that includes a first channel and a second channel. The first channel is configured as a charging channel and is configured to at least one of wirelessly receive or transmit power. The first channel is also configured to transmit network pairing information for at least one of pairing or un-pairing the first network member and a second network member. The network pairing information is transmitted over the first channel at a first frequency. The second channel is configured as an operational channel, and is configured to communicate operational information between the first and second network members when the first and second network members are paired. The operational information is transmitted over the second channel at a second frequency that is different than the first frequency.

Novel technologies and configurations of superconducting magnets for MRI

Abstract: A review of non-traditional approaches and emerging trends in superconducting magnets for MRI is presented. Novel technologies and concepts have arisen in response to new clinical imaging needs, changes in market cost structure, and the realities of newly developing markets. Among key trends are an increasing emphasis on patient comfort and the need for ?greener? magnets with reduced helium usage. The paper starts with a brief overview of the well-optimized conventional MR magnet technology that presently firmly occupies the dominant position in the imaging market up to 9.4?T. Non-traditional magnet geometries, with an emphasis on openness, are reviewed. The prospects of MgB2 and high-temperature superconductors for MRI applications are discussed. In many cases the introduction of novel technologies into a cost-conscious commercial market will be stimulated by growing needs for advanced customized procedures, and specialty scanners such as orthopedic or head imagers can lead the way due to the intrinsic advantages in their design. A review of ultrahigh-field MR is presented, including the largest 11.7?T Iseult magnet. Advanced cryogenics approaches with an emphasis on low-volume helium systems, including hermetically sealed self-contained cryostats requiring no user intervention, as well as future non-traditional non-helium cryogenics, are presented.

Affinity Learning with Diffusion on Tensor Product Graph

Abstract: In many applications, we are given a finite set of data points sampled from a data manifold and represented as a graph with edge weights determined by pairwise similarities of the samples. Often the pairwise similarities (which are also called affinities) are unreliable due to noise or due to intrinsic difficulties in estimating similarity values of the samples. As observed in several recent approaches, more reliable similarities can be obtained if the original similarities are diffused in the context of other data points, where the context of each point is a set of points most similar to it. Compared to the existing methods, our approach differs in two main aspects. First, instead of diffusing the similarity information on the original graph, we propose to utilize the tensor product graph (TPG) obtained by the tensor product of the original graph with itself. Since TPG takes into account higher order information, it is not a surprise that we obtain more reliable similarities. However, it comes at the price of higher order computational complexity and storage requirement. The key contribution of the proposed approach is that the information propagation on TPG can be computed with the same computational complexity and the same amount of storage as the propagation on the original graph. We prove that a graph diffusion process on TPG is equivalent to a novel iterative algorithm on the original graph, which is guaranteed to converge. After its convergence we obtain new edge weights that can be interpreted as new, learned affinities. We stress that the affinities are learned in an unsupervised setting. We illustrate the benefits of the proposed approach for data manifolds composed of shapes, images, and image patches on two very different tasks of image retrieval and image segmentation. With learned affinities, we achieve the bull's eye retrieval score of 99.99 percent on the MPEG-7 shape dataset, which is much higher than the state-of-the-art algorithms. When the data points are image patches, the NCut with the learned affinities not only significantly outperforms the NCut with the original affinities, but it also outperforms state-of-the-art image segmentation methods.

Capacitor Voltage Regulation in Single-DC-Source Cascaded H-Bridge Multilevel Converters Using Phase-Shift Modulation

Abstract: Cascaded H-bridge multilevel power electronic converters generally require several dc sources. An alternative option is to replace all the separate dc sources feeding the H-bridge cells with capacitors, leaving only one H-bridge cell with a real dc voltage source. This will yield a cost-effective converter. However, the required capacitor voltage balancing is challenging. In this paper, using the phase-shift modulation approach, a new control method for cascaded H-bridge multilevel converters fed with only one independent dc source is presented. The proposed method has a wide voltage regulation range for the replacement capacitors in the H-bridge cells. Experimental and simulation results support the proposed control method.

Radio tomographic imaging and tracking of stationary and moving people via kernel distance

Abstract: Network radio frequency (RF) environment sensing (NRES) systems pinpoint and track people in buildings using changes in the signal strength measurements made by a wireless sensor network. It has been shown that such systems can locate people who do not participate in the system by wearing any radio device, even through walls, because of the changes that moving people cause to the static wireless sensor network. However, many such systems cannot locate stationary people. We present and evaluate a system which can locate stationary or moving people, without calibration, by using kernel distance to quantify the difference between two histograms of signal strength measurements. From five experiments, we show that our kernel distance-based radio tomographic localization system performs better than the state-of-the-art NRES systems in different non line-of-sight environments.

Quantification of Muscle Fat in Patients with Low Back Pain: Comparison of Multi-Echo MR Imaging with Single-Voxel MR Spectroscopy

Abstract: Muscle fat fractions derived from multi-echo three-dimensional MR imaging closely match those from MR spectroscopy.

Study of the cofactor conditions: Conditions of supercompatibility between phases

Abstract: The cofactor conditions, introduced in James and Zhang(2005) , are conditions of compatibility between phases in martensitic materials. They consist of three subconditions: (i) the condition that the middle principal stretch of the transformation stretch tensor U is unity ( λ 2 = 1 ), (ii) the condition a · U cof ( U 2 − I ) n = 0 , where the vectors a and n are certain vectors arising in the specification of the twin system, and (iii) the inequality tr U 2 + det U 2 − ( 1 / 4 ) | a | 2 | n | 2 ≥ 2 . Together, these conditions are necessary and sufficient for the equations of the crystallographic theory of martensite to be satisfied for the given twin system but for any volume fraction f of the twins, 0 ≤ f ≤ 1 . This contrasts sharply with the generic solutions of the crystallographic theory which have at most two such volume fractions for a given twin system of the form f⁎ and 1 − f ⁎ . In this paper we simplify the form of the cofactor conditions, we give their specific forms for various symmetries and twin types, we clarify the extent to which the satisfaction of the cofactor conditions for one twin system implies its satisfaction for other twin systems. In particular, we prove that the satisfaction of the cofactor conditions for either Type I or Type II twins implies that there are solutions of the crystallographic theory using these twins that have no elastic transition layer. We show that the latter further implies macroscopically curved, transition-layer-free austenite/martensite interfaces for Type I twins, and planar transition-layer-free interfaces for Type II twins which nevertheless permit significant flexibility (many deformations) of the martensite. We identify some real material systems nearly satisfying the cofactor conditions. Overall, the cofactor conditions are shown to dramatically increase the number of deformations possible in austenite/martensite mixtures without the presence of elastic energy needed for coexistence. In the context of earlier work that links the special case λ 2 = 1 to reversibility ( Cui et al., 2006 , Zhang et al., 2009 , Zarnetta et al., 2010 ), it is expected that satisfaction of the cofactor conditions for Type I or Type II twins will lead to further lowered hysteresis and improved resistance to transformational fatigue in alloys whose composition has been tuned to satisfy these conditions.

A small animal Raman instrument for rapid, wide-area, spectroscopic imaging

Abstract: Raman spectroscopy, amplified by surface enhanced Raman scattering (SERS) nanoparticles, is a molecular imaging modality with ultra-high sensitivity and the unique ability to multiplex readouts from different molecular targets using a single wavelength of excitation. This approach holds exciting prospects for a range of applications in medicine, including identification and characterization of malignancy during endoscopy and intraoperative image guidance of surgical resection. The development of Raman molecular imaging with SERS nanoparticles is presently limited by long acquisition times, poor spatial resolution, small field of view, and difficulty in animal handling with existing Raman spectroscopy instruments. Our goal is to overcome these limitations by designing a bespoke instrument for Raman molecular imaging in small animals. Here, we present a unique and dedicated small-animal Raman imaging instrument that enables rapid, high-spatial resolution, spectroscopic imaging over a wide field of view (> 6 cm2), with simplified animal handling. Imaging of SERS nanoparticles in small animals demonstrated that this small animal Raman imaging system can detect multiplexed SERS signals in both superficial and deep tissue locations at least an order of magnitude faster than existing systems without compromising sensitivity.

Raising Awareness of Sleep as a Healthy Behavior

Abstract: Sleep is an essential component of health, and its timing, duration, and quality are critical determinants of health (1). Sleep may play an important role in metabolic regulation, emotion regulation, performance, memory consolidation, brain recuperation processes, and learning (2). Because of the importance of these functions, sleep should be viewed as being as critical to health as diet and physical activity. However, public health practitioners and other health care providers have not focused major attention on the importance of sleep to health. In this essay, we briefly summarize the scientific literature about hours of sleep needed and why sleep is an important public health issue. We also suggest areas for expanding sleep research and strategies for increasing awareness of the importance of sleep and improving sleep health. Finally, we call for action to bring sleep to the forefront of public health.

On the Causes of Circulating Currents in PWM Drives With Open-End Winding AC Machines

Abstract: Electric drives with open-end winding ac machines offer certain advantages over drives with star- or delta-connected machines. Such drives have been recently considered for some applications such as electric vehicles. Circulating currents have been experimentally observed in such open-end winding ac drives. These currents have the effect of increasing conduction losses in the stator winding resistance of the ac machine. Two major causes for these currents have been identified as device voltage drops in power semiconductor devices and dead time used for shoot-through current protection. These effects are analyzed, and a mathematical description for predicting their severity is provided. Experimental results are presented that support the theory. The theory developed should be useful for devising solutions for this problem such as the design of common-mode filters. Two methods of suppressing the circulating currents are also outlined, and their experimental results are presented.

System and method of improving emission performance of a gas turbine

Abstract: A power generation system (10) and method of generating power with reduced NO x emission includes a gas turbine system (15). The turbine system (15) includes a compressor (16) configured to receive a feed oxidant stream (14) and supply a compressed oxidant stream (18) to a combustion chamber (20) and an expander (24) configured to receive a discharge stream (22) from the combustion chamber (20) and generate an exhaust stream (30) comprising carbon dioxide and electrical energy. The system (10) further includes an exhaust gas recirculation system (54) configured to generate a recycle stream (52), wherein the recycle stream (52) is mixed with a fresh oxidant (12) to generate the feed oxidant stream (14). The exhaust gas recirculation system (54) includes an exhaust gas recirculation control loop (60) to control a pilot ratio (diffusion to total fuel ratio) based on received feedback related to combustion parameters. The control loop (60) is configured to control the pilot ratio required to keep NO x in its minimum ratios with improved flame stability.

Discovery of the surface polarity gradient on iridescent Morpho butterfly scales reveals a mechanism of their selective vapor response

Abstract: For almost a century, the iridescence of tropical Morpho butterfly scales has been known to originate from 3D vertical ridge structures of stacked periodic layers of cuticle separated by air gaps. Here we describe a biological pattern of surface functionality that we have found in these photonic structures. This pattern is a gradient of surface polarity of the ridge structures that runs from their polar tops to their less-polar bottoms. This finding shows a biological pattern design that could stimulate numerous technological applications ranging from photonic security tags to self-cleaning surfaces, gas separators, protective clothing, sensors, and many others. As an important first step, this biomaterial property and our knowledge of its basis has allowed us to unveil a general mechanism of selective vapor response observed in the photonic Morpho nanostructures. This mechanism of selective vapor response brings a multivariable perspective for sensing, where selectivity is achieved within a single chemically graded nanostructured sensing unit, rather than from an array of separate sensors.

Operational performance assessment of additive manufacturing

Abstract: A method for assessment of operational performance of a 3D manufacturing apparatus is provided. Images are obtained, in real-time during a 3D polymer printing build process in which at least one structure is built by the 3D manufacturing apparatus, the images being of an area of a build platform on which the at least one structure is built. The obtained images are evaluating, and it is determined, based on the evaluating, whether an operational flaw with the 3D manufacturing apparatus has occurred. Operational flaws include errors in the operation of the 3D manufacturing apparatus and/or component thereof, as evidenced by, for instance, distortions or other errors in the structure(s) being built and/or materials being used.

Networked Coordination-Based Distributed Model Predictive Control for Large-Scale System

Abstract: A class of large-scale systems, which is naturally divided into many smaller interacting subsystems, is usually controlled by a distributed or decentralized control framework. In this case, how to improve the performance of the entire system is a problem. A novel distributed model predictive control (MPC) is proposed for improving the global performance. Each subsystem is controlled by a subsystem-based MPC. These controllers coordinate with each other through global performance optimization index, and take the interactions among subsystems into account when predicting states evolution. The stability analysis for the unconstrained distributed MPC is given for guiding the control parameters tuning. Numeric results show that the proposed architecture could guarantee satisfactory global performance under even strong interactions among subsystems.

System for supplying a working fluid to a combustor

Abstract: A system for supplying a working fluid to a combustor includes a fuel nozzle, a combustion chamber 40 downstream from the fuel nozzle, and a flow sleeve 50 that circumferentially surrounds the combustion chamber 40. A plurality of fuel injectors 60 are circumferentially arranged around the flow sleeve 50 to provide fluid communication through the flow sleeve 50 to the combustion chamber 40. A distribution manifold 62 circumferentially surrounds the plurality of fuel injectors 60, and a fluid passage 66 through the flow sleeve 50 and into the distribution manifold 62 provides fluid communication through the flow sleeve 50 to the plurality of fuel injectors 60.